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A collapsible and expandable stent body includes a generally tubular
annulus section, one or more prosthetic valve elements mounted to the
stent body, and a cuff attached to the stent body. The prosthetic valve
is operative to allow flow in an antegrade direction but to substantially
block flow in a retrograde direction. The prosthetic heart valve may
include paravalvular leak mitigation features in the form of first and
second sealing members. The sealing members are attached to the cuff and
extend circumferentially around an abluminal surface of the stent body.
The sealing members each have an open side facing in a first axial
direction and a closed side facing in an opposite second axial direction.
Flow of blood in the second axial direction will tend to force blood into
the sealing members and cause the sealing members to billow outwardly
relative to the stent body, helping to mitigate paravalvular leak.

1. A prosthetic heart valve, comprising: a stent including a generally
tubular annulus section defining a first circumferential row of cells and
a plurality of commissure attachment features, the stent extending in a
longitudinal direction from an inflow end to an outflow end; one or more
prosthetic valve elements mounted to commissure attachment features of
the stent and operative to allow flow in an antegrade direction but to
substantially block flow in a retrograde direction through the annulus
section; a cuff attached to the stent and positioned on a luminal surface
of the stent; and a plurality of sealing members individually attached to
the cuff, the sealing members having an open side facing in a first axial
direction and a closed side facing in a second axial direction opposite
to the first axial direction so that a flow of blood in the second axial
direction around an ablumenal surface of the stent will tend to force
blood into the sealing members and cause the sealing members to billow
outwardly relative to the stent, wherein selected cells in the first
circumferential row of cells include cell portions that are aligned with
corresponding commissure attachment features in the longitudinal
direction of the stent, the sealing members being positioned
substantially within the selected cells in the first circumferential row,
all remaining cells in the first circumferential row excluding the
sealing members.

2. The prosthetic heart valve of claim 1, wherein each of the sealing
members has a shape chosen from the group consisting of generally
triangular, generally trapezoidal, and generally semicircular.

3. The prosthetic heart valve of claim 1, wherein at least one of the
sealing members is not directly attached to the stent.

4. The prosthetic heart valve of claim 1, wherein at least one of the
sealing members is attached to both the cuff and the stent.

5. The prosthetic heart valve of claim 1, wherein the first
circumferential row of cells is positioned at the inflow end of the
stent.

6. The prosthetic heart valve of claim 5, wherein the stent includes a
second circumferential row of cells positioned between the inflow end of
the stent and the commissure attachment features.

7. The prosthetic heart valve of claim 6, wherein selected cells in the
second circumferential row of cells include cell portions that are
directly attached to corresponding commissure attachment features, the
sealing members being positioned substantially within the selected cells
in the second circumferential row, all remaining cells in the second
circumferential row excluding the sealing members.

8. The prosthetic heart valve of claim 1, wherein the sealing members are
formed of tissue.

9. The prosthetic heart valve of claim 8, wherein the tissue includes
fibers having a predominant fiber orientation extending in the
longitudinal direction of the stent.

10. The prosthetic heart valve of claim 8, wherein the tissue includes
fibers having a predominant fiber orientation extending in a
circumferential direction of the stent.

11. The prosthetic heart valve of claim 8, wherein the tissue includes
fibers having a predominant fiber orientation extending in a direction
between the longitudinal direction of the stent and a circumferential
direction of the stent.

12. The prosthetic heart valve of claim 1, wherein the open sides of the
sealing members are punctuated by closed portions to create a plurality
of reduced-size openings.

13. The prosthetic heart valve of claim 12, wherein the closed portions
of the open sides of the sealing members are formed by stitches.

14. A prosthetic heart valve, comprising: a stent including a generally
tubular annulus section defining a plurality of cells; one or more
prosthetic valve elements mounted to the stent and operative to allow
flow in an antegrade direction but to substantially block flow in a
retrograde direction through the annulus section; a cuff attached to the
stent and positioned on a luminal surface of the stent; and a plurality
of sealing members attached to the cuff, the sealing members having an
open side facing in a first axial direction and a closed side facing in a
second axial direction opposite to the first axial direction so that a
flow of blood in the second axial direction around an ablumenal surface
of the stent will tend to force blood into the sealing members and cause
the sealing members to billow outwardly relative to the stent, wherein
the open sides of the sealing members are punctuated by closed portions
to create a plurality of reduced-size openings.

15. The prosthetic heart valve of claim 14, wherein the closed portions
of the open sides of the sealing members are formed by stitches.

16. The prosthetic heart valve of claim 14, wherein the plurality of
sealing members are each individually attached to the cuff.

17. The prosthetic heart valve of claim 14, wherein the plurality of
sealing members include one or more groups of continuous series of
sealing members.

18. The prosthetic heart valve of claim 14, wherein each of the sealing
members has a shape chosen from the group consisting of generally
triangular, generally trapezoidal, and generally semicircular.

19. The prosthetic heart valve of claim 14, wherein the closed side of
each of the sealing members is straight and non-pointed.

20. The prosthetic heart valve of claim 14, wherein the closed side of
each of the sealing members is curved and non-pointed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a continuation of U.S. patent
application Ser. No. 15/148,322, filed May 6, 2016, which is
continuation-in-part of U.S. patent application Ser. No. 14/501,200 filed
Sep. 30, 2014 and issued as U.S. Pat. No. 9,668,857 on Jun. 6, 2017,
which claims the benefit of the filing date of U.S. Provisional Patent
Application No. 61/900,475 filed Nov. 6, 2013, the disclosures of which
are all hereby incorporated by reference herein.

[0003] Prosthetic heart valves that are collapsible to a relatively small
circumferential size can be delivered into a patient less invasively than
valves that are not collapsible. For example, a collapsible valve may be
delivered into a patient via a tube-like delivery apparatus such as a
catheter, a trocar, a laparoscopic instrument, or the like. This
collapsibility can avoid the need for a more invasive procedure such as
full open-chest, open-heart surgery.

[0004] Collapsible prosthetic heart valves typically take the form of a
valve structure mounted on a stent. There are two types of stents on
which the valve structures are ordinarily mounted: a self-expanding stent
and a balloon-expandable stent. To place such valves into a delivery
apparatus and ultimately into a patient, the valve must first be
collapsed or crimped to reduce its circumferential size.

[0005] When a collapsed prosthetic valve has reached the desired implant
site in the patient (e.g., at or near the annulus of the patient's heart
valve that is to be replaced by the prosthetic valve), the prosthetic
valve can be deployed or released from the delivery apparatus and
re-expanded to full operating size. For balloon-expandable valves, this
generally involves releasing the valve, assuring its proper location, and
then expanding a balloon positioned within the valve stent. For
self-expanding valves, on the other hand, the stent automatically expands
as the sheath covering the valve is withdrawn.

[0006] Clinical success of a self-expanding valve may be at least
partially dependent on accurate deployment and sealing. For example,
inaccurate deployment and anchoring may result in the leakage of blood
between the implanted heart valve and the native valve annulus, commonly
referred to as perivalvular or paravalvular leakage ("PV leak"). In
aortic valves, this leakage enables blood to flow from the aorta back
into the left ventricle, reducing cardiac efficiency and putting a
greater strain on the heart muscle. Additionally, calcification of the
aortic valve may affect performance and the interaction between the
implanted valve and the calcified tissue is believed to be relevant to
leakage. Additionally, in certain procedures, collapsible valves may be
implanted in a native valve annulus without first resecting the native
valve leaflets.

BRIEF SUMMARY

[0007] One aspect of the present disclosure relates to mechanisms and
features for prosthetic valves to facilitate sealing against paravalvular
leaks. These mechanisms may include, for example, patches or other types
of material that expand or billow open upon PV leak to create a better
seal between the prosthetic valve and the native tissue in which the
prosthetic valve is implanted.

[0008] In one embodiment of the disclosure, a prosthetic heart valve
includes a stent body including a generally tubular annulus section
defining a first circumferential row of cells. The prosthetic heart valve
may include one or more prosthetic valve elements mounted to the stent
body and operative to allow flow in an antegrade direction but to
substantially block flow in a retrograde direction through the annulus
section. The prosthetic heart valve may further include a cuff attached
to the stent body and positioned on a luminal surface of the stent body.
At least one sealing member may be attached to the cuff, the at least one
sealing member having an open side facing in a first axial direction and
a closed side facing in a second axial direction opposite to the first
axial direction so that a flow of blood in the second axial direction
will tend to force blood into the at least one sealing member and cause
the sealing member to billow outwardly relative to the stent body. The at
least one sealing member may have a shape chosen from the group
consisting of generally triangular, generally trapezoidal, and generally
semicircular.

[0009] In another embodiment of the disclosure, a prosthetic heart valve
includes a stent body including a generally tubular annulus section
defining a first circumferential row of cells and a second
circumferential row of cells distal to the first circumferential row of
cells. The prosthetic heart valve may also include one or more prosthetic
valve elements mounted to the stent body and operative to allow flow in
an antegrade direction but to substantially block flow in a retrograde
direction through the annulus section. The prosthetic heart valve my
further include a cuff attached to the stent body and positioned on a
luminal surface of the stent body. At least one proximal sealing member
may be attached to the cuff and positioned substantially within a cell in
the first circumferential row of cells, the proximal sealing member
having an open side facing in a first axial direction and a closed side
facing in a second axial direction opposite the first axial direction so
that a flow of blood in the second axial direction will tend to force
blood into the proximal sealing member and cause the proximal sealing
member to billow outwardly relative to the stent body. At least one
distal sealing member may be attached to the cuff and positioned
substantially within a cell in the second circumferential row of cells,
the distal sealing member having an open side facing in the first axial
direction and a closed side facing in the second axial direction so that
the flow of blood in the second axial direction will tend to force blood
into the distal sealing member and cause the distal sealing member to
billow outwardly relative to the stent body.

[0010] In yet a further embodiment of the disclosure, a prosthetic heart
valve includes a stent body including a generally tubular annulus section
and one or more prosthetic valve elements mounted to the stent body and
operative to allow flow in an antegrade direction but to substantially
block flow in a retrograde direction through the annulus section. A cuff
may be attached to the stent body and positioned on a luminal surface of
the stent body. A sealing member may be attached to the cuff, the sealing
member being generally rectangular and having an open side facing in a
first axial direction and a closed side facing in a second axial
direction opposite to the first axial direction so that a flow of blood
in the second axial direction will tend to force blood into the sealing
member and cause the sealing member to billow outwardly relative to the
stent body. The sealing member may be wrapped around an entire
circumference of the stent body and define a pocket divided into a
plurality of regions, each of the regions being in fluid communication
with adjacent ones of the regions.

[0011] In still a further embodiment of the disclosure, a prosthetic heart
valve includes a stent body including a generally tubular annulus
section, and one or more prosthetic valve elements mounted to the stent
body and operative to allow flow in an antegrade direction but to
substantially block flow in a retrograde direction through the annulus
section. A cuff may be attached to the stent body and positioned on a
luminal surface of the stent body. At least one strut may form a finger
at a proximal end thereof. The finger may be configured to lie
substantially parallel to the stent body when the stent body is in a
collapsed condition and may be configured to curve radially outwardly and
distally when the stent body is in an expanded condition, the cuff being
attached to the finger.

[0012] In a further embodiment of the disclosure, a prosthetic heart valve
includes a collapsible and expandable stent body including a generally
tubular annulus section and one or more prosthetic valve elements mounted
to the stent body and operative to allow flow in an antegrade direction
but to substantially block flow in a retrograde direction through the
annulus section. A cuff may be attached to the stent body. A first
sealing member is attached to the cuff, the first sealing member
extending circumferentially around an abluminal surface of the stent body
and having an open side facing in a first axial direction and a closed
side facing in a second axial direction opposite to the first axial
direction so that a flow of blood in the second axial direction will tend
to force blood into the first sealing member and cause the first sealing
member to billow outwardly relative to the stent body. A second sealing
member is attached to the cuff, the second sealing member extending
circumferentially around the abluminal surface of the stent body and
having an open side facing in the first axial direction and a closed side
facing in the second axial direction so that the flow of blood in the
second axial direction will tend to force blood into the second sealing
member and cause the second sealing member to billow outwardly relative
to the stent body. The first sealing member may define a first pocket
having a plurality of first regions, each of the first regions being in
fluid communication with adjacent ones of the first regions. Similarly,
the second sealing member may define a second pocket having a plurality
of second regions, each of the second regions being in fluid
communication with adjacent ones of the second regions. The first sealing
member and/or the second sealing member may be wrapped around an entire
circumference of the stent body. The open side of the first sealing
member and/or the open side of the second sealing member may be attached
to the cuff at spaced locations around a circumference of the stent body.
The open side of the first sealing member may include a first plurality
of openings and the open side of the second sealing members may include a
second plurality of openings, the first plurality of openings being
offset in a circumferential direction from the second plurality of
openings. The first sealing member may be positioned nearer an inflow end
of the stent body than the second sealing member. The open side of the
first sealing member may be axially spaced apart from the closed side of
the second sealing member. The first sealing member may comprise an
extension of the cuff, the extension being wrapped around an inflow end
of the stent body such that the extension is positioned on an abluminal
surface of the stent body. A proximal portion of the extension on the
abluminal surface of the stent body may be connected to a proximal
portion of the cuff on the luminal surface of the stent body with a seam.
The first sealing member and/or the second sealing member may be formed
from a separate piece of material from the cuff. The first sealing member
and/or the second sealing member may be formed of a single piece of
material or a plurality of pieces of material. The first sealing member
and/or the second sealing member may be substantially rectangular.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a side elevational view of a conventional prosthetic
heart valve.

[0014] FIG. 2 is a highly schematic cross-sectional view taken along line
A-A of FIG. 1 and showing the prosthetic heart valve disposed within a
native valve annulus.

[0015] FIG. 3A is an enlarged partial schematic view of a sealing member
attached to a stent according to an embodiment of the disclosure.

[0016] FIG. 3B is a schematic view of an isolated individual sealing
member.

[0017] FIG. 3C is a schematic view of an isolated series of sealing
members.

[0018] FIGS. 3D-E are enlarged views showing portions of sealing members
having different fiber orientations.

[0019] FIGS. 3F-G are highly schematic longitudinal cross-sections showing
a sealing member of a valve billowing open to different extents.

[0020] FIGS. 3H-I are schematic views of isolated individual sealing
members with different shapes.

[0021] FIG. 4A is an enlarged partial schematic view of a sealing member
attached to a stent according to another embodiment of the disclosure.

[0022] FIG. 4B is an enlarged partial schematic view of a sealing member
attached to a stent according to a further embodiment of the disclosure.

[0023] FIG. 4C is a schematic view of isolated sealing members arranged in
a staggered pattern.

[0024] FIG. 5 is an enlarged partial schematic view of a sealing member
attached to a stent according to still another embodiment of the
disclosure.

[0025] FIG. 6A is a highly schematic partial longitudinal cross-section of
a sealing member attached to a stent, with the stent in an expanded
configuration, according to yet another embodiment of the disclosure.

[0026] FIG. 6B is a highly schematic partial longitudinal cross-section of
the sealing member and stent of FIG. 6A in a collapsed configuration.

[0027] FIG. 7 is an enlarged partial schematic view of two sealing members
attached to a stent according to yet a further embodiment of the
disclosure.

[0028] Various embodiments of the present disclosure will now be described
with reference to the appended drawings. It is to be appreciated that
these drawings depict only some embodiments of the heart valve according
to the descriptions herein and are therefore not to be considered
limiting of the scope of the present disclosure.

DETAILED DESCRIPTION

[0029] As used herein, the term "proximal," when used in connection with a
prosthetic heart valve, refers to the end of the heart valve closest to
the heart when the heart valve is implanted in a patient, whereas the
term "distal," when used in connection with a prosthetic heart valve,
refers to the end of the heart valve farthest from the heart when the
heart valve is implanted in a patient. The term "circumferential," when
used in connection with a prosthetic heart valve, refers to the direction
around the perimeter of the valve. Also, when used herein, the words
"generally" and "substantially" are intended to mean that slight
variations from absolute are included within the scope of the structure
or process recited.

[0030] FIG. 1 shows a collapsible stent-supported prosthetic heart valve
100 known in the art. The prosthetic heart valve 100 is designed to
replace the function of a native tricuspid, bicuspid or unicuspid valve
of a patient, such as a native aortic valve. It should be noted that
while the present disclosure is described predominantly in connection
with prosthetic aortic valves and a stent having a shape as illustrated
in FIG. 1, the concepts described herein may also be used with prosthetic
bicuspid valves, such as prosthetic mitral valves, and with stents having
different shapes, such as those having a flared or conical annulus
section, a less-bulbous aortic section, and the like, and a differently
shaped transition section. Examples of collapsible prosthetic heart
valves are described in International Patent Application Publication No.
WO/2009/042196; U.S. Pat. No. 7,018,406; and U.S. Pat. No. 7,329,278, the
disclosures of all of which are hereby incorporated herein by reference.

[0031] Prosthetic heart valve 100 will be described in more detail with
reference to FIG. 1. Prosthetic heart valve 100 includes expandable stent
102, which may be formed from biocompatible materials that are capable of
self-expansion, such as, for example, shape memory alloys such as
nitinol. Stent 102 extends from proximal or annulus end 130 to distal or
aortic end 132, and includes tubular annulus section 140 adjacent the
proximal end and aortic section 142 adjacent the distal end. Annulus
section 140 has a relatively small cross-section in the expanded
condition, while aortic section 142 has a relatively large cross-section
in the expanded condition. Preferably, annulus section 140 is in the form
of a cylinder having a substantially round cross-section and a
substantially constant diameter along its length. Transition section 141
may taper outwardly from annulus section 140 to aortic section 142. Each
of the sections of stent 102 includes a plurality of cells 112 connected
to one another in one or more annular rows around the stent. For example,
as shown in FIG. 1, annulus section 140 may have two annular rows of
cells 112 and aortic section 142 and transition section 141 may each have
one or more annular rows of cells. Cells 112 in aortic section 142 may be
larger than the cells in annulus section 140. The larger cells in aortic
section 142 better enable prosthetic valve 100 to be positioned in the
native valve annulus without the stent structure interfering with blood
flow to the coronary arteries.

[0032] Stent 102 may include one or more retaining elements 118 at distal
end 132 thereof, the retaining elements being sized and shaped to
cooperate with retaining structures provided on the deployment device
(not shown). The engagement of retaining elements 118 with retaining
structures on the deployment device helps maintain prosthetic heart valve
100 in assembled relationship with the deployment device, minimizes
longitudinal movement of the prosthetic heart valve relative to the
deployment device during unsheathing or resheathing procedures, and helps
prevent rotation of the prosthetic heart valve relative to the deployment
device as the deployment device is advanced to the target location and
the heart valve deployed. In some variations, retaining elements 118 may
be disposed near proximal end 130 of heart valve 100.

[0033] Prosthetic heart valve 100 includes one or more prosthetic valve
elements, such as valve assembly 104, preferably positioned in the
annulus section 140 of stent 102 and secured to the stent. Valve assembly
104 includes cuff 106 and a plurality of leaflets 108, which collectively
function as a one-way valve by coapting with one another, generally
allowing blood to flow in an antegrade direction while substantially
blocking blood from flowing in a retrograde direction. As a prosthetic
aortic valve, valve 100 has three leaflets 108. However, it will be
appreciated that other prosthetic heart valves with which the active
sealing mechanisms of the present disclosure may be used may have a
greater or lesser number of leaflets.

[0034] Although cuff 106 is shown in FIG. 1 as being disposed on the
luminal or inner surface of annulus section 140, it is contemplated that
the cuff may be disposed on the abluminal or outer surface of the annulus
section or may cover all or part of either or both of the luminal and
abluminal surfaces. Both cuff 106 and leaflets 108 may be wholly or
partly formed of any suitable biological material or polymer such as, for
example, polytetrafluoroethylene (PTFE), ultra high molecular weight
polyethylene (UHMWPE), polyethylene terephthalate (PET), silicone,
urethane, and combinations of the preceding materials.

[0035] Leaflets 108 may be attached along their belly portions to cells
112 of stent 102, with the commissure between adjacent leaflets attached
to commissure attachment features ("CAFs") 116. The particular size and
shape of CAFs 116 may vary in different valves, for example valves with
larger or smaller diameters may include CAFs that are sized or shaped
differently than the illustrated CAFs. As can be seen in FIG. 1, each CAF
116 may lie at the intersection of four cells 112 of stent 102, two of
the cells being adjacent one another in the same annular row, and the
other two cells being in different annular rows and lying in end-to-end
relationship. Preferably, CAFs 116 are positioned entirely within the
annulus section 140 of stent 102 or at the juncture of annulus section
140 and transition section 141. CAFs 116 may include one or more eyelets
which facilitate the suturing of the leaflet commissure to the stent.

[0036] Prosthetic heart valve 100 may be used to replace, for example, a
native aortic valve, a surgical heart valve, a repair device or a heart
valve that has undergone a surgical procedure. The prosthetic heart valve
may be delivered to the desired site (e.g., near the native aortic
annulus) using any suitable delivery device. During delivery, the
prosthetic heart valve is disposed inside the delivery device in the
collapsed condition. The delivery device may be introduced into a patient
using a transfemoral, transapical, transseptal, transaortic, subclavian
or any other percutaneous approach. Once the delivery device has reached
the target site, the user may deploy prosthetic heart valve 100. Upon
deployment, prosthetic heart valve 100 expands so that annulus section
140 is in secure engagement within the native aortic annulus. When the
prosthetic heart valve is properly positioned inside the heart, it works
as a one-way valve, allowing blood to flow from the left ventricle of the
heart to the aorta, and preventing blood from flowing in the opposite
direction. However, as described in greater detail below, some amount of
blood may unintentionally flow in the opposite direction around the
outside of the prosthetic heart valve due to PV leak.

[0037] FIG. 2 is a highly schematic cross-sectional illustration of
prosthetic heart valve 100 disposed within native valve annulus 250. As
seen in the figure, annulus section 140 of stent 102 has a substantially
circular cross-section which is disposed within non-circular native valve
annulus 250. It should be understood that the depiction of native valve
annulus 250 in FIG. 2, represented as diagonal lines, is not intended to
represent the anatomical shape of the native valve annulus. At certain
locations around the perimeter of heart valve 100, crescent-shaped gaps
200 form between the heart valve and native valve annulus 250. Blood
flowing through these gaps and past valve assembly 104 of prosthetic
heart valve 100 can cause regurgitation and other inefficiencies which
reduce cardiac performance. Such improper fitment may be due to bending
of stent 102 upon application of force, or due to suboptimal native valve
annulus geometry due, for example, to calcification of native valve
annulus 250 or to unresected native leaflets. Embodiments of prosthetic
heart valves disclosed herein address PV leak that may occur through gaps
200.

[0038] FIG. 3A illustrates a portion of prosthetic heart valve 300
according to an embodiment of the disclosure. In particular, prosthetic
heart valve 300 includes an active sealing mechanism for sealing against
PV leak in the form of one or more sealing members 320. In this example,
sealing members 320 take the form of parachute-like elements that billow
open when blood flows in a retrograde direction D.sub.R into the
parachute-like elements. If retrograde flow occurs on the abluminal side
of valve 300, the blood may enter one or more sealing members 320,
causing the sealing members to billow open and facilitating the sealing
of gap spaces between the patient's anatomy and the valve. It should also
be noted, for this and other embodiments described herein, sealing
members 320 may help seal a gap space between prosthetic valve 300 and
the native anatomy, even if there is little or no PV leak to cause the
sealing members to billow open. This may be due to, for example, the
additional material of sealing members 320 filling gap spaces by virtue
of the material being positioned in those gap spaces.

[0039] In the illustrated embodiment, prosthetic heart valve 300 includes
an expandable stent 302 with a plurality of CAFs 316 (only one
illustrated in FIG. 3A), which may be similar in many or all respects to
stent 102 and CAFs 116 of FIG. 1. Stent 302 extends from proximal or
annulus end 330 to a distal or aortic end (not shown), and includes
annulus section 340 adjacent the proximal end and an aortic section (not
shown) adjacent the distal end. Each of the sections of stent 302
includes a plurality of cells 312 connected to one another in one or more
annular rows around the stent. For example, as shown in FIG. 3A, annulus
section 340 may have two annular rows of cells 312, including a first
proximalmost circumferential row of cells 312a and a second
circumferential row of cells 312b distal to the first row. Valve 300 may
also include cuff 306, which may be substantially similar to cuff 106 of
FIG. 1. Preferably, cuff 306 has a relatively straight proximal end. In
the illustrated embodiment, cuff 306 is positioned on the luminal side of
stent 302 and attached to the stent, for example, by sutures (not
illustrated).

[0040] Sealing members 320 may take the form of generally triangular
patches of material, although other shapes may be suitable. The
triangular patches may be attached to cuff 306 during valve assembly, or
after valve assembly is otherwise complete. Any suitable attachment
method, such as sewing, may be used. Preferably, a distal or open side
321 of each sealing member 320, in this case the distal side of the
triangular patch, is left partially or completely unconnected to cuff
306. For example, if sewing the triangular patch to cuff 306, two
proximal sides 322, 323 of the triangle, meeting at a proximalmost point,
are sewn to the cuff, but the open side 321 of the triangle is not. With
this configuration, the open side 321 of sealing member 320 remains
capable of opening upon retrograde blood flow, with the open side facing
the distal end of valve 300. Further, the closed proximal sides 322, 323
that are connected to cuff 306 restrict blood from exiting through the
proximal sides of sealing member 320. Proximal sides 322, 323 may be sewn
such that open side 321 is loose or floppy, and not taut, thereby
enabling blood to flow into sealing member 320. As described above, if
retrograde blood flow does occur on the abluminal side of valve 300, the
parachuting or billowing action of sealing members 320 upon blood flowing
into the sealing members facilitates active sealing between the
prosthetic heart valve and the native tissue surrounding the valve.

[0041] When taking the form of triangular patches, sealing members 320 may
be individual elements, as illustrated in FIG. 3B, or a continuous series
of elements, as illustrated in FIG. 3C. With sealing members 320 that are
individual elements, a user may individually attach any desired number of
the sealing members to corresponding portions of valve 300 in any desired
pattern or location. Generally, the more sealing members 320 that are
used, the greater the profile and general bulkiness of valve 300. If
certain areas of valve 300 are particularly prone to PV leak, it may be
desirable to strategically attach individual sealing members 320 to the
valve only in those prone areas. For example, an area of valve 300
proximal to each CAF 316 may be particularly prone to PV leak. During
operation, when valve 300 is closed and the pressure distal to the valve
is greater than the pressure proximal to the valve, a proximally directed
force may cause portions of stent 302, such as CAFs 316, to pull radially
inward, exposing areas of the valve to potential PV leak. By using
individual sealing members 320 only in those areas, sealing against PV
leak may be maximized while minimizing the profile and/or bulkiness of
valve 300.

[0042] Alternatively, sealing members 320 may take the form of a plurality
of triangular patches in series. Although FIG. 3C illustrates three
sealing members 320 in series, more or less may be acceptable. For
example, if the first row 312a of cells 312 includes nine cells spanning
the circumference of annulus section 340, it may be preferable to use
nine sealing members 320 connected together as a single element. This
configuration may be particularly convenient, enabling the user to handle
only a single piece of material. In this configuration, sealing members
320 may be attached to cuff 306 such that, for each cell 312 in a
particular row of cells, one sealing member is positioned substantially
within each cell. However, this may also be achieved by attaching nine
individual sealing members 320 to cuff 306, or by using a combination of
individual sealing members and sealing members attached to one another in
series. The term "substantially within" refers to the fact that, although
each sealing member 320 is preferably positioned mostly within a
particular cell 312 such that it may billow open through the cell with
relatively little resistance, some minimal amount of the cell structure
may overlap a portion of the sealing member.

[0043] Each sealing member 320 may be attached to cuff 306, or to both the
cuff and stent body 302. Preferably, each sealing member 320 is attached
only to cuff 306 and is capable of parachuting or billowing open through
a cell 312 of stent body 302 upon blood entering the sealing member. By
attaching sealing members 320 to cuff 306 only, rather than to both the
cuff and stent body 302, the overall bulkiness and/or profile of valve
300 may be reduced.

[0044] For this and other embodiments described herein, it should also be
noted that sealing members 320, when valve 300 is implanted in a patient,
may be situated sub-annularly, intra-annularly, and/or supra-annularly.
The particular position of sealing members 320 with respect to the native
annulus may be affected by, for example, the particular position of the
sealing members on stent body 302. There may be particular advantages and
disadvantages of each position. For example, if the sealing members are
positioned supra-annularly, they may be less likely to be distorted by
the shape of the native annulus. However, this positioning may be more
likely to result in coronary blockage, a larger profile in a relatively
bulky area of the valve, and the positioning may be coincident with the
most calcified areas of the native anatomy. If the sealing members are
positioned intra-annularly, they may provide for sealing above and below
the annulus without causing other physiological issues. However, this
positioning may lead to interference with anchoring features of a
prosthetic valve, which may lead to a higher likelihood of valve
migration or a larger profile in a relatively bulky area of the valve.
Finally, if the sealing members are positioned sub-annularly, the valve
may have a relatively small profile and the sealing members may be
coincident with the least calcified portions of the native anatomy.
However, this positioning may increase the likelihood of mitral valve or
conduction interference, may require a longer delivery device and may
result in a decreased tracking ability of the valve.

[0045] A number of variables may be manipulated to change the way in
which, and how much, each sealing member 320 billows open during
retrograde blood flow. For example, the type of material forming sealing
member 320 may influence how it billows open. In particular, forming
sealing member 320 from a material with high compliance, such as tissue,
including bovine or porcine tissue, may cause the sealing member to open
to a greater extent upon retrograde blood flow in comparison to a lower
compliance material. Similarly, forming sealing member 320 from a thin
material may lead the sealing member to open to a greater extent upon
retrograde blood flow in comparison to a thicker material. The method of
attaching sealing members 320 to valve 300 may also affect how the
sealing members open. For example, loosely sewing sealing members 320 to
cuff 306, such that the sealing members have a relatively large amount of
slack, may lead the sealing members to open to a greater extent upon
retrograde blood flow in comparison to a method in which the sealing
members have relatively little slack from being sewn tightly to the cuff.

[0046] Still further, features such as orientation of fibers in the
material used to form sealing members 320 may affect performance. For
example, if sealing member 320 is formed from tissue and is attached to
valve 300 with the fibers of the tissue oriented predominantly
circumferentially, the fibers may have a spring-like effect and resist
opening. This may result in relatively little billowing of sealing member
320 upon retrograde blood flow in comparison to a sealing member attached
to the valve with tissue fibers oriented predominantly longitudinally.
Regarding the fiber orientation, FIG. 3D illustrates tissue portion
T.sub.c in which tissue fibers F.sub.c are oriented predominantly in a
direction that is substantially circumferential. That is, when sealing
member 320 is attached to valve 300, tissue fibers F.sub.c would
predominantly align along the circumferential direction of the valve.
FIG. 3E illustrates tissue portion T.sub.L in which tissue fibers F.sub.L
are oriented predominantly in a direction that is substantially
longitudinal, i.e., a direction that, when sealing member 320 is
assembled to valve 300, is substantially parallel to the longitudinal
axis of the valve. Sealing members 320 may also be formed so that the
predominant fiber orientation of the tissue is between circumferential
and longitudinal, and may provide for intermediate extents of billowing
of the sealing members. Various methods, such as polarized light
microscopy, deflection testing and/or tensioning, may be used to
determine the dominant tissue fiber orientation. The above description
regarding fiber orientation may also apply to other materials. For
example, a sealing member made from fabric may also function differently
depending on the orientation of the fibers in the fabric. However, the
difference in opening of tissue with longitudinal versus circumferential
fiber orientation may be exaggerated in comparison to the difference in
opening of fabric with longitudinal versus circumferential fiber
orientation.

[0047] FIGS. 3F-G illustrate a schematic cross-section of a portion of
valve 300 with sealing member 320' (or 320'') attached to cuff 306 and
billowed open through an open portion of stent body 302. In FIG. 3F,
sealing member 320' may, for example, be thin, with longitudinally
oriented fibers, and may be loosely sewn to cuff 306 so that the sealing
member has a relatively large amount of slack. In FIG. 3G, sealing member
320'' may, for example, be thick, with circumferentially oriented fibers,
and may be tightly sewn to cuff 306 so that the sealing member has a
relatively small amount of slack. All else being equal, a given amount of
retrograde blood flow may cause sealing member 320' of FIG. 3F to billow
open to a greater extent than sealing member 320'' of FIG. 3G. These
variables may be manipulated such that sealing member 320 opens a desired
amount upon exposure to retrograde blood flow. In fact, it may be
desirable to pre-shape the sealing members such that they have an open
configuration, but still may be crimped along with the prosthetic valve
during delivery such that, upon delivery into a final expanded
configuration, the sealing member returns to an original open shape that
tends to maximize the ability to capture retrograde blood flow therein.

[0048] Sealing member 320 may also take shapes other than generally
triangular. For example, FIG. 3H shows a sealing member 325 that has a
generally semicircular shape, while FIG. 31 shows a sealing member 326
that has a generally trapezoidal shape. However, it should be understood
that shapes other than those specifically disclosed herein may be
suitable for use as a sealing member. Considerations that may be relevant
to the suitability of such an alternate shape include the extent to which
the alternate shape matches the shape of the cell 312 through which it
billows open. For example, when attaching a sealing member with an
alternate shape to cuff 306 and inside stent body 302, the shape
preferably allows the sealing member to open through the open portion of
the particular cell 312. A sealing member with a shape similar to that of
the cell 312 through which it opens may be able to open relatively easily
upon retrograde blood flow, while the matching shape may maximize the
volume of blood capable of entering the sealing member. Further, a
sealing member with a straight, curved, or otherwise non-pointed proximal
side, such as the curved proximal side of sealing member 325 or the
straight proximal side of sealing member 326, may provide benefits over
sealing members with pointed proximal sides, such as generally triangular
sealing member 320. In particular, a pointed proximal side may tend to
cause blood trapped therein to stagnate, while a non-pointed proximal
side may reduce the tendency for blood to stagnate, thereby reducing the
likelihood of the formation of a thrombus, for example. Further, the
pointed proximal side of such a sealing member may not provide an
adequate volume into which blood may flow compared to a similar shape
with a non-pointed proximal side.

[0049] The width of the open sides of the sealing members, such as open
side 321 of sealing member 320, may also be varied. For example, the
sealing members may have wider openings than those illustrated to
maximize the likelihood of capturing retrograde blood flow. The wide
openings, or any other sealing member openings described herein, may also
alternately be punctuated by frequent stitches or other mechanisms to
close portions of the open side. The effect of frequently spaced sutures,
for example, may create a number of smaller openings that still allow
blood flow to enter the particular sealing member. However, if a thrombus
forms within the sealing member, the reduced sized openings may make it
less likely that the thrombus may exit the sealing member into the blood
flow.

[0050] FIG. 4A illustrates a portion of prosthetic heart valve 400
according to another embodiment of the disclosure. Prosthetic heart valve
400 may be similar or identical to prosthetic heart valve 300 in all
respects other than the active sealing mechanism. For example, prosthetic
heart valve 400 includes an expandable stent 402 with a plurality of CAFs
416 (only one illustrated in FIG. 4A). Stent 402 extends from proximal or
annulus end 430 to a distal or aortic end (not shown), and includes
annulus section 440 adjacent the proximal end and an aortic section (not
shown) adjacent the distal end. Each of the sections of stent 402
includes a plurality of cells 412 connected to one another in one or more
annular rows around the stent. For example, as shown in FIG. 4A, annulus
section 440 may have two annular rows of cells 412, including a first
proximalmost row of cells 412a and a second row of cells 412b distal to
the first row. Valve 400 may also include cuff 406, which may be
substantially similar to cuff 306 of FIG. 3A. In the illustrated
embodiment, cuff 406 is positioned on the luminal side of stent 402 and
attached to the stent, for example, by sutures (not illustrated).

[0051] Prosthetic heart valve 400 includes sealing members 420 that
provide an active sealing mechanism for sealing against PV leak. Similar
to valve 300, the sealing members 420 take the form of generally
triangular patches or parachute-like members that billow open when blood
flows into them. However, valve 400 includes proximal sealing members
420a positioned along the first row of cells 412a as well as distal
sealing members 420b positioned along the second row of cells 412b. All
of the considerations discussed above with respect to sealing members 320
of FIG. 3A apply with equal force to sealing members 420a and 420b of
FIG. 4A. Sealing members 420b on the second row of cells 412b may provide
for additional sealing against PV leak. For example, points at which open
sides 421a of two adjacent sealing members 420a meet may be less likely
to catch retrograde blood flow. In the illustrated embodiment, a second
row of sealing members 420b is positioned such that center portions of
the open sides 421b of sealing members 420b generally align
longitudinally with points at which open sides 421a of two adjacent
sealing members 420a meet. In other words, the position of the center of
open sides 421a of the first row of sealing members 420a is
circumferentially staggered or offset from the position of the center of
open sides 421b of the second row of sealing members 420b. This
configuration may decrease the likelihood that retrograde blood flow will
travel proximally between two adjacent sealing members 420a without being
caught in any sealing member.

[0052] As described with respect to sealing members 320, sealing members
420a, 420b may be individually attached to cuff 406, or multiple sealing
members may first be connected to one another in a series for
convenience. For example, in one embodiment, sealing members 420a, 420b
may be attached to cuff 406 at each cell 412 in the first and second rows
of cells 412a, 412b, respectively. Also as described with respect to
sealing members 320, sealing members 420a, 420b may be placed
strategically on valve 400 to maximize sealing against PV leak while
minimizing the number of the sealing members, and therefore minimizing
the bulk of the valve. One embodiment that may be particularly effective,
illustrated in FIG. 4B, includes only a single sealing member 420b on the
cells 412 in the second row of cells 412b that are directly proximal to
each CAF 416. For each sealing member 420b on the second row of cells
412b, two sealing members 420a are positioned on the first row of cells
412a below the sealing member 420b, such that the center portion of the
open side 421b of the sealing member 420b generally aligns longitudinally
with the point at which the open sides 421a of the adjacent sealing
members 420a meet.

[0053] A number of alternate configurations of sealing members may be
utilized. As described above, sealing members, such as sealing members
420a and 420b, may be positioned on the inner diameter of stent body 402,
that is, between the stent body and cuff 406. However, they may
alternately be placed on the outer diameter of stent body 402. If
positioned on the outer diameter, more shapes and configurations may be
used since the sealing members no longer need to be capable of billowing
open through the open cells of stent body 402. Rather, if on the outer
diameter of stent body 402, the positions of open cells of stent body 402
do not limit the shape or configuration of the sealing members at all.
For example, FIG. 4C illustrates a schematic view of sealing members
420a, 420b arranged in a staggered pattern, with the remainder of
prosthetic valve 400 not illustrated. In this configuration, a first row
of sealing members 420a is positioned in a staggered relationship with a
second row of sealing members 420b. Open sides 421a of sealing members
420a are positioned proximally relative to open sides 421b of sealing
members 420b. However, there is some overlap between sealing members
420a, 420b. In particular, open sides 421a of sealing members 420a are
positioned approximately at a midline of sealing members 420b. In other
words, the proximal-to-distal distance between open sides 421b and 421a
is approximately equal to the proximal-to-distal distance between open
sides 421a of sealing members 420a and the proximalmost points of sealing
members 420b. These distances may be varied, however, to increase or
decrease the level of staggering and overlap between sealing members 420a
and 420b. It should further be noted that, in this particular embodiment,
it may be preferable for sealing members 420a, 420b to be attached to the
outer diameter of stent body 402, rather than between the stent body 402
and cuff 406. This may be preferable if the shape and position of sealing
members 420a, 420b does not match with the shape and position of the open
cells of stent body 402 such that the sealing members may easily billow
open through the open cells. By staggering sealing members 420a, 420b,
the profile of valve 400 may be reduced in comparison to a configuration
in which sealing members 420a, 420b are aligned in a single non-staggered
row. Still further, it should be noted that in the embodiments described
herein, one row, two rows, or more rows of sealing members may be
suitable for use with a prosthetic heart valve.

[0054] FIG. 5 illustrates a portion of prosthetic heart valve 500
according to a further embodiment of the disclosure. Prosthetic heart
valve 500 may be similar or identical to prosthetic heart valves 300 and
400 in all respects other than the active sealing mechanism. For example,
prosthetic heart valve 500 includes an expandable stent 502 with a
plurality of CAFs 516 (only one illustrated in FIG. 5). Stent 502 extends
from proximal or annulus end 530 to a distal or aortic end (not shown),
and includes annulus section 540 adjacent the proximal end and an aortic
section (not shown) adjacent the distal end. Each of the sections of
stent 502 includes a plurality of cells 512 connected to one another in
one or more annular rows around the stent. For example, as shown in FIG.
5, annulus section 540 may have two annular rows of cells 512, including
a first proximalmost row of cells 512a and a second row of cells 512b
distal to the first row. Valve 500 may also include a cuff 506, which may
be substantially similar to cuffs 306 and 406 of FIGS. 3A and 4A,
respectively. In the illustrated embodiment, cuff 506 is positioned on
the luminal side of stent 502 and attached to the stent, for example, by
sutures (not illustrated).

[0055] Prosthetic heart valve 500 includes a sealing member 520 that
provides an active sealing mechanism for sealing against PV leak. Sealing
member 520 may take the form a rectangular patch that functions as a
parachute-like member that billows open when blood flows into it. In the
illustrated embodiment, sealing member 520 includes an open distal side
521 and a closed proximal side 522. The proximal side 522 of sealing
member 520 may be attached, for example by sewing, to cuff 506. The
attachment is preferably such that blood entering sealing member 520
cannot exit through the closed proximal side 522 of the sealing member.
In this configuration, sealing member 520 defines a pocket. The pocket
may include regions defined by the points at which sealing member 520
near the open side 521 is attached to cuff 506, as described below. Each
region of the pocket may be in fluid communication with adjacent regions.
The rectangular patch may be wrapped around the entire circumference of
stent 502 with ends of the patch attached to one another to secure the
patch in a desired position. In this embodiment, sealing member 520 is a
separate entity from cuff 506. Further, in this embodiment, sealing
member 520 is preferably attached over the outside of both cuff 506 and
stent 502 to allow the sealing member to billow open. This is in contrast
to other embodiments, such as generally triangular sealing members 320,
which preferably are attached between cuff 306 and stent 302 and which
are capable of billowing open through cells 312 of the stent.

[0056] One or more individual rectangular patches may be individually
attached to stent 502 such that the collective patches are wrapped
partially, or entirely, around the circumference of the stent. Portions
of sealing member 520 near the open side 521 are also preferably attached
to cuff 506, for example using sutures S. As illustrated, a small number
of stitches, such as two or three, connect distal portions of sealing
member 520 to cuff 506 at spaced locations around the circumference of
the sealing member. While the sutures S are shown as attaching sealing
member 520 to cuff 506 along portions of the struts where adjacent cells
512a meet, the connections may be made at any point on the cuff. The
distal attachments preferably are few enough to leave a substantial
portion of open side 521 free such that retrograde blood flow may freely
flow into sealing member 520, while still providing enough support to
maintain the position of the distal end of the sealing member relative to
cuff 506. Similar to embodiments described above, if blood flows in the
retrograde direction, represented by arrows D.sub.R, on the abluminal
side of the valve 500, the blood may flow into sealing member 520 between
the points at which the sealing member is attached to cuff 506. The blood
may enter and fill sealing member 520, causing it to expand similar to an
inner tube, facilitating the creation of a seal against PV leak between
valve 500 and the native tissue in which the valve is positioned.

[0057] Sealing member 520 may alternately be formed as an extension of
cuff 506, rather than one or more separate rectangular patches. For
example, cuff 506, which is positioned on the luminal side of valve 500,
may include a portion which extends beyond the proximal end of stent 502.
This extending portion may be folded or wrapped around the proximal end
of stent 502 such that the extending portion is on the abluminal side of
valve 500. The extending portion would form sealing member 520 and would
otherwise act similarly to separate rectangular patches attached to cuff
506. In this embodiment, in which sealing member 520 is an extension of
cuff 506, it may not be necessary to suture or otherwise attach the
proximal end of the sealing member to the cuff, since the sealing member
is an extension of the cuff. However, it still may be preferable to form
a seam, for example with a suture, between sealing member 520 and cuff
506 adjacent the proximal ends thereof. This may, for example, provide
structural support to sealing member 520.

[0058] FIG. 6A illustrates a sealing member 620 according to another
embodiment of the disclosure. FIG. 6A is a highly schematic sectional
view of a proximal portion of a stent body 602 for use in a prosthetic
heart valve. As illustrated, a strut of stent body 602 extends proximally
from CAF 616 to a proximal end of the stent, at which point the strut
transitions into a finger 650 that curves radially outwardly and distally
in a general "J" shape. In other words, the strut forms finger 650 at a
proximal end of the strut. Cuff 606 may be attached on the luminal side
of stent 602 and extend toward the proximal end of the stent, and then
curve back up radially outwardly and distally, following the contour of
finger 650. In this embodiment, cuff 606 may extend partially or
completely around the circumference of stent 602, attached to a discrete
number of fingers 650. This embodiment functions similarly to the
embodiment described above in which sealing member 520 forms an extension
of cuff 506 that is folded or wrapped over the proximal end of stent 502.
However, the use of fingers 650 may be beneficial, as the arms may be set
to curve outwardly only after stent 602 is deployed and transitions from
a collapsed condition to an expanded condition. For example, FIG. 6B
illustrates stent 602 and finger 650, along with cuff 606 and sealing
member 620, prior to deployment when it is in a collapsed condition, for
example within a delivery device. In this configuration, finger 650 lies
substantially flat with respect to stent body 602. This configuration
allows for the collapsed profile to remain relatively small, since finger
650 and sealing member 620 do not curve outwardly until stent 602 is
released from a delivery device and transitions into the expanded
condition illustrated in FIG. 6A. Once in the expanded condition,
retrograde blood flowing into the sealing member 620 may cause the
sealing member to expand further or fill up like an inner tube, helping
to create a seal between the valve and the native tissue in which the
valve is implanted.

[0059] FIG. 7 illustrates a portion of prosthetic heart valve 700
according to a further embodiment of the disclosure. Prosthetic heart
valve 700 may be similar or identical to prosthetic heart valve 500 in
most respects. For example, prosthetic heart valve 700 includes an
expandable stent 702 with a plurality of CAFs 716 (only one illustrated
in FIG. 7). Stent 702 extends from a proximal or annulus end 730 to a
distal or aortic end (not shown), and includes annulus section 740
adjacent the proximal end and an aortic section (not shown) adjacent the
distal end. It should be understood that, when implanted in a native
aortic or pulmonary valve, the proximal end may be referred to as the
inflow or inlet end, and the distal end may be referred to as the outflow
or outlet end. It should further be understood that, if placed in a
native atrioventricular valve such as the mitral valve, a proximal end of
the stent may be referred to as an outflow end.

[0060] Each of the sections of stent 702 includes a plurality of cells 712
connected to one another in one or more annular rows around the stent.
For example, as shown in FIG. 7, annulus section 740 may have two annular
rows of cells 712, including a first proximalmost row of cells 712a and a
second row of cells 712b distal to the first row. Valve 700 may also
include a cuff 706, which may be substantially similar to cuff 506 of
FIG. 5. In the illustrated embodiment, cuff 706 is positioned on the
luminal side of stent 702 and attached to the stent, for example, by
sutures (not illustrated).

[0061] Prosthetic heart valve 700 includes sealing members 720a, 720b that
provide an active sealing mechanism for sealing against PV leak. Sealing
members 720a and 720b may each take a similar or identical form as
sealing member 520 of prosthetic heart valve 500. For example, sealing
member 720a may be a rectangular patch that functions as a parachute-like
member that billows open when blood flows into it. In the illustrated
embodiment, sealing member 720a includes an open distal side 721a and a
closed proximal side 722a. The proximal side 722a of sealing member 720a
may be attached, for example by sewing, to cuff 706. The attachment is
preferably such that blood entering sealing member 720a cannot exit
through the closed proximal side 722a of the sealing member. In this
configuration, sealing member 720a defines a pocket. The pocket may
include regions defined by the points at which sealing member 720a near
the open side 721a is attached to cuff 706, as described below. Each
region of the pocket may be in fluid communication with adjacent regions.
The rectangular patch may be wrapped around the entire circumference of
stent 702 with ends of the patch attached to one another to secure the
patch in a desired position. In this embodiment, sealing member 720a is a
separate entity from cuff 706. Further, in this embodiment, sealing
member 720a is preferably attached over the outside of both cuff 706 and
stent 702 to allow the sealing member to billow open.

[0062] Sealing member 720a may take the form of a single rectangular
patch, or multiple patches connected to one another to form a rectangular
patch that is long enough to extend around the entire circumference of
annulus portion 740. Portions of sealing member 720a near the open side
721a are also preferably attached to cuff 706, for example using sutures
S1. As illustrated, a small number of stitches, such as two or three,
connect distal portions of sealing member 720a to cuff 706 at spaced
locations around the circumference of the sealing member. In particular,
the sutures S1 may be placed near where one cell 712a meets a
circumferentially adjacent cell 712a, so that the pocket formed in
sealing member 720a has a plurality of openings, each of which having a
width substantially equal to a maximum circumferential width of a cell
712a when stent 702 is in the expanded condition. While the sutures S1
are shown as attaching sealing member 720a to cuff 706 along portions of
the struts where adjacent cells 712a meet, the connections may
alternatively be made at any point on the cuff. The distal attachments
preferably are few enough to leave a substantial portion of open side
721a free such that retrograde blood flow may freely flow into sealing
member 720a, while still providing enough support to maintain the
position of the distal end of the sealing member relative to cuff 706.

[0063] Valve 700 may include a second sealing member 720b, which may take
the form of a rectangular patch similar or identical to sealing member
720a (or similar to any described alternative way to form sealing member
720a). Sealing member 720b may be positioned mostly or entirely distal to
sealing member 720a, so that a closed proximal side 722b of sealing
member 720b is positioned adjacent to or spaced apart from the open
distal side 721a of sealing member 720a. Closed proximal side 722b may be
attached to cuff 706 with sutures or any other suitable fastening
mechanism so that blood entering sealing member 720b from the open side
721b is unable to exit sealing member 720b through the closed side 722b.
Similar to sealing member 720a, the open side 721b of sealing member 720b
may be coupled to cuff 706 and/or struts of stent 702 at
circumferentially spaced apart locations to form a plurality of openings
leading into the pocket of sealing member 720b. In the illustrated
embodiment, sutures S2 attach portions of the distal side of sealing
member 720b at locations of cuff 706 and/or stent 702 at which a cell
712b in the second circumferential row meets a circumferentially adjacent
cell 712b in that same row. With this configuration, the openings in open
side 721b of sealing member 720b generally correspond to the maximum
width of a cell 712b in the expanded condition of stent 702. This allows
for circumferential positional staggering of the openings in the open
side 721b of sealing member 720b compared to the openings in the open
side 721a of sealing member 720a.

[0064] Similar to embodiments described above, if blood flows in the
retrograde direction, represented by arrows D.sub.R, on the abluminal
side of valve 700, the blood may flow into sealing member 720a between
the points at which the sealing member is attached to cuff 706. The blood
may enter and fill sealing member 720, causing it to expand similar to an
inner tube, facilitating the creation of a seal against PV leak between
valve 700 and the native tissue in which the valve is positioned. To the
extent that retrograde blood flow is less likely to enter sealing member
720a at the positions at which open side 721a is sutured to the cuff 706
and/or stent 702, such retrograde blood flow may be likely to enter
sealing member 720b since the corresponding locations of open side 721b
of sealing member 720b will be free to open and receive retrograde blood
flow. In other words, the use of two sealing members 720a-b with the
attachment locations described above may provide for similar additional
capability of mitigating PV leak as described in connection with the
circumferentially staggered patches 421a-b of FIG. 4A.

[0065] Similar to sealing member 520, first sealing member 720a may
alternately be formed as an extension of cuff 706, with cuff 706
including a portion which extends beyond the inflow edge of stent 702.
This extending portion may be folded or wrapped around the inflow edge of
stent 702 such that the extending portion is on the abluminal side of
valve 700. The extending portion would form first sealing member 720 and
would otherwise act similarly to a rectangular patch attached to cuff
706. In this embodiment, in which first sealing member 720a is an
extension of cuff 706, it may not be necessary to suture or otherwise
attach the proximal end of the first sealing member 720a to the cuff 706,
since the sealing member is an extension of the cuff. However, it still
may be preferable to form a seam, for example with a suture, between
first sealing member 720a and cuff 706 adjacent the proximal ends
thereof. This may, for example, provide structural support to first
sealing member 720a.

[0066] Still further, first sealing member 720a and/or second sealing
member 720b may be configured to wrap around only a part of the
circumference of stent 702. This may allow, for example, strategic
placement of sealing members 720a and/or 720b to maximize the likelihood
of the sealing members 720a and/or 720b receiving retrograde blood flow
while minimizing the amount of material and bulk added to valve 700. In
one example of this, similar to the embodiment described in connection
with FIG. 4B, second sealing member 720b may extend partially around the
circumference of stent 702 proximal to the CAFs 716, with first sealing
member 720a extending partially around the circumference of stent 702
proximal to CAFs 716 and proximal to second sealing member 720b. In this
embodiment, first sealing member 720a and second sealing member 720b may
each comprise a plurality of individual patches, such as rectangular
patches, positioned to catch retrograde blood flow on the abluminal side
of stent 702 near the CAFs, which area may be particularly susceptible to
PV leak, as described above in connection with FIG. 4B. It should be
understood if some other portion of valve 700 is determined to be
particularly susceptible to PV leak, the sealing members 720a and/or 720b
may be positioned at those locations to increase the likelihood of
mitigating such PV leak.

[0067] According to one aspect of the disclosure, a prosthetic heart valve
comprises: [0068] a collapsible and expandable stent body including a
generally tubular annulus section; [0069] one or more prosthetic valve
elements mounted to the stent body and operative to allow flow in an
antegrade direction but to substantially block flow in a retrograde
direction through the annulus section; [0070] a cuff attached to the
stent body; [0071] a first sealing member attached to the cuff, the first
sealing member extending circumferentially around an abluminal surface of
the stent body and having an open side facing in a first axial direction
and a closed side facing in a second axial direction opposite to the
first axial direction so that a flow of blood in the second axial
direction will tend to force blood into the first sealing member and
cause the first sealing member to billow outwardly relative to the stent
body; and [0072] a second sealing member attached to the cuff, the second
sealing member extending circumferentially around the abluminal surface
of the stent body and having an open side facing in the first axial
direction and a closed side facing in the second axial direction so that
the flow of blood in the second axial direction will tend to force blood
into the second sealing member and cause the second sealing member to
billow outwardly relative to the stent body; and/or [0073] the first
sealing member defines a first pocket having a plurality of first
regions, each of the first regions being in fluid communication with
adjacent ones of the first regions; and/or [0074] the second sealing
member defines a second pocket having a plurality of second regions, each
of the second regions being in fluid communication with adjacent ones of
the second regions; and/or [0075] the first sealing member is wrapped
around an entire circumference of the stent body; and/or [0076] the
second sealing member is wrapped around the entire circumference of the
stent body; and/or [0077] the open side of the first sealing member is
attached to the cuff at spaced locations around a circumference of the
stent body; and/or [0078] the open side of the second sealing member is
attached to the cuff at spaced locations around the circumference of the
stent body; and/or [0079] the open side of the first sealing member
includes a first plurality of openings and the open side of the second
sealing members includes a second plurality of openings, the first
plurality of openings being offset in a circumferential direction from
the second plurality of openings; and/or [0080] the first sealing member
is positioned nearer an inflow end of the stent body than the second
sealing member; and/or [0081] the open side of the first sealing member
is axially spaced apart from the closed side of the second sealing
member; and/or [0082] the first sealing member comprises an extension of
the cuff, the extension being wrapped around an inflow end of the stent
body such that the extension is positioned on an abluminal surface of the
stent body; and/or [0083] a proximal portion of the extension on the
abluminal surface of the stent body is connected to a proximal portion of
the cuff on the luminal surface of the stent body with a seam; and/or
[0084] the second sealing member is formed from a separate piece of
material from the cuff; and/or [0085] the first sealing member is formed
from a separate piece of material from the cuff; and/or [0086] the first
sealing member is formed of a single piece of material; and/or [0087] the
second sealing member is formed of a single piece of material; and/or
[0088] the first sealing member is formed from a plurality of pieces of
material; and/or [0089] the second sealing member is formed from a
plurality of pieces of material; and/or [0090] the first sealing member
is substantially rectangular; and/or [0091] the second sealing member is
substantially rectangular.

[0092] Although the prosthetic valves herein have been described with
reference to particular embodiments, it is to be understood that these
embodiments are merely illustrative of the principles and applications of
the present invention. It is therefore to be understood that numerous
modifications may be made to the illustrative embodiments and that other
arrangements may be devised without departing from the spirit and scope
of the present invention as defined by the appended claims.

[0093] It will be appreciated that the various dependent claims and the
features set forth therein can be combined in different ways than
presented in the initial claims. It will also be appreciated that the
features described in connection with individual embodiments may be
shared with others of the described embodiments.